Georgetown & Howard Universities

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Course Overview

The Georgetown-Howard Universities Center for Clinical and Translational Science is delighted to sponsor and support a three-day power and sample size workshop. The short course, taught by Keith E. Muller, Ph.D., professor in the University of Florida College of Medicine, and Deborah H. Glueck, Ph.D., associate professor in the University of Colorado School of Public Health, will give scientists training for selecting a valid sample size for longitudinal and multilevel study designs. The workshop is accessible to all, from graduate students to senior researchers, and requires only basic statistical background.


Host Location Date Registration Deadline
Georgetown & Howard Universities Louis Stokes Health Sciences Library, Room 138
(See #200 on map)
Mon., Aug. 28, 2017 – Wed. Aug. 30, 2017 Mon., Aug. 21, 2017


Before Sat., July 1, 2017: $500
Before Tues., Aug. 1, 2017: $750
Tues., Aug. 1, 2017 through Mon., Aug. 21, 2017: $1,000

Special pricing of $750 is available for those at educational institutions, non-profits, or government offices. In addition, we may be able to provide partial support to help defray costs for a limited number of attendees who are members of historically under-represented minorities with demonstrated financial need. In either case, please contact for more details.


To register for the course, click here.

For questions, please contact Sandra Salloum, academic specialist, at

Workshop Objectives

At the end of the workshop, attendees will be able to:

  • Understand a framework and strategy for study planning
  • Write study aims as testable hypotheses
  • Describe a longitudinal and multilevel study design
  • Write a statistical analysis plan
  • Ensure sufficient sample size for subgroups for studies of disparities
  • Demonstrate the feasibility of recruitment
  • Describe expected missing data and dropout
  • Write a power and sample size analysis that is aligned with the planned statistical analysis
  • Write the design, analysis, power and sample size sections for a grant
  • Use expert feedback to improve the product

Workshop Schedule

This workshop will take place in the Louis Stokes Health Sciences Library, Room 138 from 9 a.m. – 5 p.m. The schedule below details each day’s agenda.

Day 1: Study Design
  • 9 a.m.-12 p.m.: Understanding four common study designs and factors in experimental design
  • 12-1 p.m.: Instructional workshop on the ethics of power and sample size
  • 1-2 p.m.: Optional accessible walk and talk with faculty or break time
  • 2-5 p.m.: Understanding the hypothesis, linking study designs to statistical models and understanding types of study outcomes
Day 2: Power and Sample Size Analysis
  • 9 a.m.-12 p.m.: Choosing the appropriate statistical test, understanding correlation structure in multilevel and longitudinal studies, understanding power and Type I error and aligning power analysis and data analysis
  • 12-1 p.m.: Working lunch with faculty on class projects or optional break
  • 1-2 p.m.: Optional accessible walk and talk with faculty or break time
  • 2-5 p.m.: Summarizing a study design, predicting missing data and dropout and accounting for missing data and dropout
Day 3: Writing the Grant
  • 9 a.m.-12 p.m.: Collecting inputs for power analysis, studying power via statistical simulation, demonstrating recruitment feasibility and handling multiple study aims
  • 12- 1 p.m.: Working lunch with faculty on class projects or optional break
  • 1-2 p.m.: Optional accessible walk and talk with faculty or break time
  • 2-5 p.m.: Writing the sample size section for your grant, graphics for power and sample size, power for subgroup analysis and getting funded
Post-Class Assignments
  • Four homework assignments
  • One two-hour in-person or online lab to receive guidance on assignments 1-4
  • Final assignment
  • Consisting of a one-page statistical analysis plan and power or sample size analysis
  • Three hours of in-person or online lab to receive help on final assignment.
  • One-hour interactive video conference via GoToMeeting with students and workshop instructors


The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Materials for the course were developed with support from NIH OBSSR and NIGMS via 1R25GM111901-01, “A Master Course on Power for Multilevel and Longitudinal Health Behavior Studies,” 08/25/2014-06/30/2018. Additional support was provided by the Center for Bioethics and Humanities of the University of Colorado Denver, the University of Florida (UF) Clinical and Translational Science Institute, the UF Department of Health Outcomes and Policy, and Federal funds (UL1TR001409) from the National Center for Advancing Translational Services (NCATS), National Institutes of Health, through the Clinical and Translational Science Awards Program (CTSA), a trademark of DHHS, part of the Roadmap Initiative, “Re-Engineering the Clinical Research Enterprise.